Vízügyi Közlemények, 1965 (47. évfolyam)

4. füzet - Rövidebb közlemények és beszámolók

'(14) study performed with the help of the TN factor—for which a numerical example based of the Danube is given—comprises the main relations influencing the draft of the stationary vessel and thus the utilization of its carrying capacity. Since the hydrographie, ice, fog, high stage, etc. conditions of the waterway are also involved in the TN factor, certain problems can already be solved with the statistical method. TN factor studies performed for a given vessel, waterway, or section of waterway offer information on the "weight" of loss of utilizable cargo space caused by ice, flood, or insufficient water depth. The study can be performed for vessels of different type on the same waterway, or for the same vessel on different waterways, so that waterways, or sections offering for a given type of vessel optimum potential capacity, or conversely the types of vessel ensuring the highest TN factor on a given waterway can be selected. The method is represented also in a graphical manner and reference is made to the possibility of classification (Fig. 1 ). In the second part of the paper a dynamic approach is made to the waterway (the moving water) and to carrying capacity (vessel). Introducing further the concept of "time equivalent", allowance is made for including into the potential kilometre distance the main factors influencing navigation, such as round the clock, or daytime operation, one-, or twoway navigation, the presence of restricted sections, etc. Besides Eq. (2) expressing the TK-factor (ton-kilometre), two diagrams are given for determining the potential kilometre distances which can be absolved by vessels over a given waterway, or section in upstream and downstream operation separately (Figs. 2 and 3 ). The Tk-factor obtained by substituting the corresponding parameters is representative in a complex manner for the main parameters of the waterway as well as for the nautical, engineering, hydrometeorological and morphological properties thereof affecting navigation. The TK-factor is thus the resultant of the 15 main parameters listed in the paper and indicative from the point of view of vessel operation for the extent to which carrying capacity can be exploited dynamically over the waterway or section under consideration. A numerical example is hereafter presented to illustrate the TK-factor investigation performed on the Danube river for a certain type of vessel. It is pointed out that time equivalents quoted are assumed values and that for comparing waterways of various regions on a uniform basis actual values should be determined on a international level. The method presented by the author is suitable for expansion in different directions. By establishing a logical sequence for the correlation of parameters influencing navigation a means has been created for performing numerous engineering and economical studies. The classification of waterways and sections according to dynamical utilization potential of carrying capacity, i. е., according to the TK-factor is suggested. By establishing appropriate "ТК-classes" waterways could be evaluated (classified) on the basis of the resulting effect of all parameters influencing navigation. The TK-factor study performed before and after canalization of a waterway would throw light on the effect of canalization on navigation. An example on this is given for the Upper Danube, naturally again with assumed conditions. DETERMINATION OF THE OPTIMUM YIELD OF THERMAL SPRINGS By B. Spiriev, Eng. (For the Hungarian text see pp. 55) A method is presented for determining the optimum yield which can be produced from wells discharging hot water. The notions involved are defined and explained first. The volume of free water in the aquifer is referred to as static resources [Eqs. (1) and (2)]. The quantity of water resulting from the expansion of water volume and reduction of pore volume in the depression zone around the well is termed elastic resources [Eqs. (3) and (4)]. Dynamic resources are defined as the rate of seepage flow through a cross section perpendicular to the direction of underground flow. The optimum production yield is understood as the part of static, elastic and dynamic underground water resources